The present disclosure relates to an active matrix-type liquid crystal display device.
As a conventional active matrix-type liquid crystal display device, the liquid crystal display device which is described in Japanese Unexamined Patent Application Publication No. 2004-125895 (Patent Document 1) is known. Patent Document 1 describes an active matrix-type liquid crystal display device in which a transistor is arranged as an active element on each crossing portion where row scanning lines and column data lines cross at right angles. The liquid crystal display device described in Patent Document 1 holds a pixel signal in a signal holding capacitor through each of the transistors, and drives a liquid crystal in accordance with the held pixel signal.
A parasitic capacitance is formed between a gate terminal and source terminal of the transistor. This parasitic capacitance varies a source voltage when the transistor shifts from a conducting state to a non-conducting state. When the source voltage of the transistor varies, a flicker, horizontal streak noise or the like become prone to occur in an event of driving the liquid crystal, and the image quality degrades.
In order to suppress such a degrading of the image quality, a capacitor is provided in a location close to an output portion of a scanning circuit that scans each of the row scanning lines in the conventional liquid crystal display device. Through this capacitor, a rise and a fall of a row selection signal given to the gate terminal of the transistor becomes gradual, and a variation of the source voltage of the transistor is suppressed.